Sherman is definitely not a safe place for beginners or someone flying an unfamiliar kite to launch kites - you have to trek down a trail with logs, rocks, and shrubs to get to landing/takeoff pad. Plus getting off the island requires immediately upwind skills for the general wind direction.

the wind is strong and the river moves fast.... its a strange treadmill effect, you can ride super small kites because the water is pushing you up wind. think about it, the water runs towards the ocean at 5-8knts and the wind blows upriver at 25kts+. the gorge is not a beginner friendly spot, its more difficult then Sherman. do you research before blindly entering the water there.

Lessons at Sherman are great - they will take you upwind ~1 mile to a very nice launch so you have a long ways to go before needing to get picked up by the boat again. Going there without lessons is a whole 'nother story though...